El Niño Could Bring More Widespread Coral Bleaching, NOAA Warns The National Oceanic and Atmospheric Administration (NOAA) has warned that the expected arrival of El Niño in the coming months could trigger another mass coral bleaching event, similar to the one that concluded last year. This potential event would be the fifth global bleaching incident on record, with reefs in the northern Pacific, including Hawaii, as well as those around Florida and the Caribbean, at high risk. Scientists attribute the increasing frequency of these events to climate change and rising ocean temperatures, noting that defining the start and end of global bleaching is becoming more difficult.

• El Niño’s expected arrival could trigger a new mass coral bleaching event this summer.
• This would be the fifth global bleaching incident in recorded history.
• Reefs in the northern Pacific (including Hawaii), Florida, and the Caribbean are at high risk.
• Scientists link the increasing frequency of bleaching events to climate change and rising ocean temperatures.
• Defining the start and end of global bleaching events is becoming more challenging.
• The last global bleaching event impacted 84% of the world’s reefs.
• Strong El Niño events since 1998 have coincided with global bleaching events.
• NOAA is studying heat tolerance in corals to improve restoration strategies.